Produce Degradation Pathways and Prevention

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270 Produce Degradation: Reaction Pathways and their Prevention


of the substance by 1°C. The large amount of heat energy required to raise the
temperature of water is due to the multiple hydrogen bonds that occur between
several water molecules. As the temperature of water is raised, the water molecules
vibrate, and therefore a great deal of energy must be put into the system to break
the hydrogen bonds between water molecules. Taiz and Zeiger (1998) concluded
that this large energy input requirement is important for plants because it helps slow
potentially harmful temperature fluctuations. Steinbeck (1995) described thermal
conductivity as another important property of water and attributed this to the highly
ordered structure of water. Due to this high thermal conductivity, water rapidly
conducts heat from the point of application and, in conjunction with specific heat,
facilitates the absorption and redistribution of large amounts of heat without much


FIGURE 9.1 Water molecule structure model showing the hydrogen bond, charges, and angles.

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